The Additive Effect of ROCK Inhibitor on Prostaglandin-Treated Japanese Patients with Glaucoma Indicating 15 mmHg and Under: ROCK U-15.

INTRODUCTION

We aimed to evaluate the additional effects and safety of a Rho-associated protein kinase (ROCK) inhibitor, ripasudil hydrochloride hydrate, in Japanese patients with primary open-angle glaucoma (POAG) with an intraocular pressure (IOP) of at most 15 mmHg undergoing prostaglandin F2α (FP) receptor agonist monotherapy (FP monotherapy).

METHODS

In this prospective observational study, 30 Japanese patients with POAG and IOP of at most 15 mmHg (mean age 59.4 years; 10 men) who were undergoing FP monotherapy in both eyes were administered an additional dose of ripasudil hydrochloride hydrate (GLANATEC ophthalmic solution 0.4%: ripasudil) in one eye. The following factors were investigated at 1 and 3 months after the initiation of ripasudil treatment: (1) magnitude of change in IOP between the treated and contralateral untreated eyes, (2) number of treated eyes showing 20% and 30% IOP reduction, (3) IOP difference between treated and contralateral untreated eyes, and (4) safety during the treatment period. Both (1) and (3) were analyzed using the mixed-effect model for repeated measurements.

RESULTS

The treated eyes showed significant reduction in IOP at 1 month (- 1.92 mmHg, P < 0.001) and 3 months (- 1.81 mmHg, P < 0.001). In contrast, contralateral untreated eyes did not show IOP reduction at 1 month (0.53 mmHg, P = 0.016) and 3 months (0.38 mmHg, P = 0.15). IOP reduction of - 20% and - 30% was achieved in 9 (30%) and 3 (10%) treated eyes, respectively. There were significant differences in IOP between the treated and contralateral untreated eyes at 1 month (- 2.46 mmHg, P < 0.001) and 3 months (- 2.20 mmHg, P < 0.001). Two patients experienced local adverse events (facial edema, one patient at week 1; blepharitis, one patient at 1 month); they recovered quickly after stopping ripasudil administration.

CONCLUSION

In patients with POAG with an IOP of at most 15 mmHg undergoing FP monotherapy, the addition of ripasudil resulted in significant IOP lowering at 1 and 3 months. Ripasudil could be used to enhance the outcome of FP monotherapy.

TRIAL REGISTRATION: Registered UMIN ID: UMIN000030742.